Braudel has been faulted for the imprecision of his approach. With his Rabelaisian delight in concrete detail, Braudel vastly extended the realm of relevant phenomena; but this very achievement made it difficult to delimit the boundaries of observation, a task necessary to beginning any social investigation. Further, Braudel and other Annales historians minimize the differences among the social sciences. Nevertheless, the many similarly designed studies aimed at both professional and popular audiences indicate that Braudel asked significant questions which traditional historians had overlooked.
In a similar way, he argued that it is impossible to understand the events of the reign of Philip II without placing them in the perspective of the long term – ‘ la longue durée ’, as he calls it: a perspective of centuries, or even, in the case of the geographical section of the book, of millennia. Insofar as this huge book has a general argument, it is that time moves at different speeds, and that it is useful to distinguish three ‘temporalities’ in particular. There is the short term, the time of events, time as it is perceived by contemporaries; the middle term, the time of ‘economic systems, states, societies, civilisations’; and finally, the very long term, the ‘almost timeless history’ of man’s relation to the environment. In a sense, this argument simply made explicit themes in the work of earlier historians, among them Febvre, who had long been interested in historical geography, and Bloch, who had written both economic history and the history of mentalities over the long term. Yet there can be little doubt that Braudel’s formulation, and his example, have been extremely influential on the history written in France and elsewhere over the last thirty years or so.
His followers admired his use of the longue durée approach to stress the slow and often imperceptible effects of space, climate and technology on the actions of human beings in the past.  The Annales historians, after living through two world wars and massive political upheavals in France, were very uncomfortable with the notion that multiple ruptures and discontinuities created history. They preferred to stress inertia and the longue durée , arguing that the continuities in the deepest structures of society were central to history. Upheavals in institutions or the superstructure of social life were of little significance, for history, they argued, lies beyond the reach of conscious actors, especially the will of revolutionaries. They rejected the Marxist idea that history should be used as a tool to foment and foster revolutions.  A proponent of historical materialism, Braudel rejected Marxist materialism, stressing the equal importance of infrastructure and superstructure, both of which reflected enduring social, economic, and cultural realities. Braudel's structures, both mental and environmental, determine the long-term course of events by constraining actions on, and by, humans over a duration long enough that they are beyond the consciousness of the actors involved.